Ladder unit for venetian blinds



' Jan. 3, 1939. V

s. H. HiNLEIN ET AL 2,142,900

LADDER UNIT FOR VENETIAN BLINDS Filed May 25 1956 3 Sheets-Sheet 1 Jan. 3, 1939. s. H. HINLEIN ET AL LADDER UNIT FOR YENETIANBLINDS Filed May 25, 1936 5 Sheets-Sheet 3 Patented Jan. 3, 1939 NITED STATES PATENT OFFICE Stanley H. mulch and Milton J. Hinlein,

Elkins Park, Pa.; said Stanley H. Hinlein assignor to said Milton J. Hinlcin Application May 25, 1936, Serial No. 81,725

9 Claims.

This invention relates to ladder structures or tapes such as are used in Venetian blinds for supporting the slats thereof in substantially horizontal parallel relation to each other.

6 Heretofore, the ladder tapes of Venetian blinds have been made of woven fabric and consisted of two vertically hanging side strips arranged in laterally spaced parallel relation to each other and connected by cross or rung strips having their 30 opposite ends secured to the fabric of the side strips respectively. In some instances the ladder tape including the woven side strips and the woven cross strips have been woven as a unit, 1. e. the side strips and cross strips have been 115. woven simultaneously in superposed relation to each other on a multi-shuttle loom. In some instances, this mode of procedure in addition to requiring the use of a more or less complicated loom involves aiurther disadvantage in that a hand or machine operation is necessary in order to sever the strip of fabric which constitutes the cross strips at spaced intervals throughout the length of the tape, where the material constituting the cross strips passes from the material constituting one side strip to the material constituting the other side strip, in order that the side strips can be spread apart laterally.

In other instances, instead of the cross strips being of a woven character they merely consist of floating warps disposed between the superposed side strips during weaving and connected to said side strips alternately at relatively spaced points along said side strips. This method of procedure also involves the manual operation of cutting the floating warps at predetermined points in order to permit the side strips to be separated laterally.

The above noted operations necessarily slow down production and add expense to the production of the tape units.

The object of the present invention is to produce a ladder fabric unit in a single operation and in such a manner as to eliminate the necessity for hand or mechanical clipping operations, whereby the unit may be produced at a greater rate and at less expense than has been possible heretofore.

The construction of the unit andthe process by which it is manufactured and by which the above object is made possible will be described in detail hereinafter, reference being had to the accompanying drawings, of which:

Fig. l diagrammatically illustrates a ladder tape made in accordance with the principles of U the present invention and in which the side strips of the ladder are laid in flat parallel relation to each other in substantially the same position assumed during the making of the tape;

Fig. 2 is a transverse sectionalview taken on the line 2-2, Fig. 1; Fig. 3 illustrates the unit of Fig. 1 as it would appear when installed in a blind with the side strips disposed in parallel laterally spaced planes respectively;

Fig. 4 is a transverse section taken on the line 4-4, Fig. 3;

Fig. 5 diagrammatically illustrates the construction of the tape; I

Fig. 6 is a view similar to Fig. 1, illustrating a modified form of the invention;

Fig.7 is a view similar to Fig. 4 and illustrates the unit of Fig. 6 when installed in a blind, and

Fig. 8 is a fragmentary view of a portion of the strip shown in Fig. 6 and drawn to an enlarged scale.

As shown in Figs. 1 to 5, the ladder fabric unit I comprises a pair of similar side strips 2 and-3 respectively which are integrally connected one to the other at spaced intervals throughout the length thereof by cross rungs 4, 4, it being noted that the opposite ends of the runs 4, 4 are connected to the side strips 2 and 3 respectively substantially at the longitudinal center lines of the strips 2 and 3, as indicated at 5, 5.

In that form of the invention shown in Figs. 1 to 5, the side strips 2 and 3 are formed of a knitted fabric. In the present instance the knitted fabric of strips 2 and 3 is of the type commonly referred to as warp knit fabric. However, it will be understood that this particular type of fabric is shown merely for the purpose of illustration and that the fabric of the strips 2 and 3 may be of the type wherein all of the successive courses and adjacent'wales of stitches of which the fabric is composed are formed of a single 40 thread laid to the needles across the full width of each strip toform the fabric course by course, instead of a separate thread being employed toform each stitch Wale of the fabric as illustrated in Fig. 5.

As illustrated in Fig. 5, the strips 2 and 3 are composed of a plurality of wales or chains ak and a k respectively. Obviously, any desired number of wales or chains may be included in each strip side depending upon the width of the strip and the general character thereof which is desired.-

In the present instance the chains or wales w-k, (l -k are tied together laterally of the strips 2 and 3 by weft threads y.-y respectively ill which are laid in the succeeding courses 1-3: and l --:z: respectively, said weft threads being laid back and forth in said courses as clearly illustrated in Fig. and tying said chains a to k, a to k together to form the strips 2 and 3 respectively.

While the weft threads 1 1/ are illustrated as constituting a single thread unit in each instance, it will be readily understood that this is merely for the purpose of illustration and that in practice the wefts may be either single threads or groups of threads or a single cord made of a plurality of strands depending upon the character of the goods desired.

The rungs 4, 4 of the ladder, according to the principles of the present invention, are composed of a series of thread units 6, 'l and 8 respectively. Each of said thread units, like the wefts y--y may be in the form of a group of threads running parallel or twisted together to form a cord. Furthermore, the thread units 6, 1 and 8 may each be in the form of a single element or composed of a plurality of strands twisted together.

In the preferred form of the invention, however, the thread units 6, I and 8 are separate and distinct, for purposes which will hereinafter become apparent, but which, however, combine to form the rung 4, in each instance, which extends from the center chain f of the side strip 2 to the center chain of the side strip 3, said rungs being tied in to said chains at the points 5, 5 as illustrated at Fig. 5 and floating freely across the chains g to k and a to 9 respectively.

The thread units 6, l and 8 in order to distribute their bulk throughout the strips 2 and 3 are independently incorporated in single chains or pairs of chains lying to one side or the other of the center chains f and f in the strips 2 and 3 respectively. For example, as illustrated in Fig. 5, the unit 6 is laid in the course w of the strip 2 and crosses and is tied in to the chains 7, e, d, c, and b. The thread unit 1 is likewise laid in the course 11; and crosses and is tied into the chains f, e and d. The thread unit 8 is tied into the chain I only in wale w, but in the preceding courses '0, u, t, etc., passes back and forth across the chain and is tied in at predetermined courses between the rungs 4, 4. The thread unit 1 in the preceding courses 1), u, 1, etc., passes across and is tied into an adjacent pairbf chains (1 and e at predetermined courses between the rungs 4, 4. The thread unit 6 passes back and forth across the pair of adjacent chains 12 and c and is tied in at predetermined courses between the rungs 4, 4.

In a like manner the thread unit 6 crosses and recrosses the chain fl in the side strip 3, being tied in at predetermined courses between the rungs 4, 4. The thread unit 1, 1 passes back and forth across an adjacent pair of chains 9 and h and the thread unit 8 passes back and forth across and is tied into an adjacent pair of chains i and 7' the tying in of said units taking place at predetermined courses between the rungs 4, 4.

In the above manner the rungs 4 may be of any desired weight and the bulk of the weight may be distributed as desired in the side strips 2 and 3 without affecting the flatness of said side strips.

It will be understood, however, that if desired the thread units 6, l and 8, or a single unit comprising such a plurality of units or strands, may be incorporated in the center chains or wales 1 and f solely, in the same manner as the unit 8 when desired.

In a ladder fabric constructed as above described, when installed in a blind in the manner illustrated in Figs. 3 and 4, the rungs 4, 4 are disposed in a common plane centrally bisecting the strips 2 and 3 and arranged directly one above the other, with the opposite ends of the rungs respectively connecting the center portions of the side strips 2 and 3 as illustrated, for example in Fig. 4. In such cases the ropes 8, which are commonly employed to raise and lower the slats l0, may pass first to one side of one rung 4 and to the opposite side of the next rung alternately throughout the blind.

Ordinarily the cross strips of the ladder tapes of Venetian blinds are arranged in staggered relation to each other and the ropes 8 pass in a plane intermediate the planes of the staggered cross strips respectively.

If it is desired to stagger the rungs 4 as made in accordance with the principles of the present invention, the ends of said rungs may be attached to any of the warp chains at either side of the center chains f and f in alternating relation to each other throughout the length of the side strips 2 and 3, without departing from the spirit of the invention.

A structure with staggered rungs is disclosed clearly in Figs. 6, 7 and 8, wherein the side strips 2a and 3a, instead of being composed of a series of chains, solely, are constructed of two strips of previously woven braided or knitted material and include, parallel to the longitudinal edges of each strip, knitted chains a, b", c 2', 7', k; a e c i 7' and k respectively.

The rungs 4a in this instance are connected at their opposite ends at 5a, 5a to the strips 2a and 30. respectively, by being incorporated in one or another of the plurality of chains disposed adjacent the opposite longitudinal edges of the strips 2a and 3a. For example, alternate rungs 4a are connected to the chains adjacent the outer edges respectively of the flattened unit I a while the intermediate rungs 4a are connected at their opposite ends to the chains lying adjacent the inner adjacent edges of the strips 2a and 3a respectively which constitute the flattened tape I a, the inner connection between the thread units constituting the rungs 4a with the plurality of chains being clearly illustrated in detail in Fig. 8.

As shown in Fig. 7 when the ladder structure is installed in a blind, the side strips 2a and 3a lie in substantially parallel laterally spaced planes and are connected by the rungs 4a, 4a which are divided into two series, alternate rungs in one series and intermediate rungs in the other series, with the slat-operating rope 9 disposed in a plane intermediate the planes of the two series of rungs, as clearly illustrated in Fig. 7.

In the form of the invention shown in Fig. 6 the rings 4a are composed of individual lengths of cord, for example, with their opposite ends connected to the tapes 2a and 3a, by being caught into the stitch chains adjacent the edges of said strips. However, said rungs may be composed of a single length of cord, etc., laid back and forth across the plurality of chains and tied in to the strips 2a and So at relatively spaced or predetermined courses of stitches of which the chains are formed, as illustrated in. broken lines in Fig. 6, said running of the rung-forming thread unit back and forth across a plurality of chains in each instance being accomplished in the same general manner as any one of the thread units 6, I or 8 illustrated in Fig. 5.

We claim:

1. A ladder fabric for Venetian blinds comprising a pair of laterally spaced side strips respectively composed of knitted fabric and cross rungs connecting said strips and incorporated in the knitted fabric of said strips at the opposite ends respectively of said cross rungs.

2. A ladder fabric for Venetian blinds comprising a pair of laterally spaced side strips respectively composed of warp knit fabric including a plurality of substantially parallel warp chains and cross rungs connecting said strips and incorporated in the knitted fabric of said strips at the opposite ends respectively of said cross rungs.

3. A ladder fabric for Venetian blinds comprising a pair of laterally spaced side strips respectively composed of warp knit fabric including a plurality of substantially parallel warp chains and weft threads crossing and knit into said chains respectively and cross rungs connecting said strips and incorporated in the knitted fabric of said strips at the opposite ends respectively of said cross rungs.

4. A ladder fabric for Venetian blinds comprising a pair of laterally spaced side strips re-' spectively composed of warp knit fabric including a plurality of substantially parallel warp chains and weft threads crossing and incorporated in said chains respectively and cross rungs comprising at least one thread unit connecting said strips and incorporated in the knitted fabric of predetermined stitches of predetermined warp chains of said strips at the opposite ends respectively of said cross rungs.

5. A ladder fabric for Venetian blinds comprising a pair of laterally spaced side strips respectively composed of warp knit fabric including a plurality of substantially parallel warp chains and weft threads crossing and incorporated in said chains respectively and cross rungs comprising a plurality of thread units connecting said strips and incorporated in the knitted fabric of predetermined stitches of predetermined warp chains of said strips at the opposite ends respectively of said cross rungs.

6. A ladder fabric for Venetian blinds comprising a pair of laterally spaced side strips composed of knitted fabric respectively composed of warp knit fabric including a plurality of substantially parallel warp chains and weft threads crossing and incorporated in said chains respectively and cross rungs comprising a plurality of thread units connecting said strips and respectively incorporated in the knitted fabric at difierent predetermined stitches of different adjacently disposed warp chains of said strips at the opposite ends respectively of said cross rungs.

7. A knitted ladder fabric for Venetian blinds comprising a pair of laterally spaced side strips and cross rungs connecting said strips and incorporated in the knitted fabric at the longitudinal central portions of said strips at the opposite ends respectively of said cross rungs.

8. A ladder fabric for Venetian blinds comprising a pair of laterally spaced side strips re-' spectively composed of knitted fabric and cross rungs comprising at least one thread unit connecting said strips and incorporated in the knitted fabric at one course of stitches of each of said strips at the opposite ends respectively of said cross rungs in at least one stitch wale of each strip and in predetermined courses and wales of each strip intermediate said rungs longitudinally of said strips.

9. A ladder fabric for Venetian blinds comprising a pair of laterally spaced side strips respectively composed of knitted fabric and cross rungs comprising a plurality of thread units 'connecting said strips and incorporated in the kintted fabric at the longitudinal central portions of said strips'at the opposite ends respectively of said cross rungs with said thread units intermediate said rungs longitudinally of said strips being respectively incorporated with different adjacently disposed stitch wales in predetermined stitch courses between said rungs.

STANLEY H. HINLEIN. MILTON J. HINLELN. 

